It’s the phenomenon by which your browser proposes a secure connection to an internet server. Sometimes the client, and therefore, the server cannot establish the connection via the protocol. That’s when an SSL handshake failure occurs. This failure often occurs in Apigee Edge. The client, unfortunately, receives the HTTP status 503 with the text “Service Unavailable”.
SOURCE: https://dzone.com/articles/ssl-handshake-failed-error-how-to-solve
OTHER SOURCE:
https://ldapwiki.com/wiki/SSL Handshake Failed
